From RepRap blog:
The Foresight Institute has announced its Kartik M. Gada Humanitarian Innovation Prize to design and build a better RepRap. There is an interim prize of $20,000, and a grand prize of $80,000. They consulted with the core RepRap team before the announcement and we were initially concerned that the prizes might drive developers to secrecy in order to give themselves a competitive edge. As you will see they have addressed those concerns by making it a condition of winning the prize that solutions should be pre-published and made available under a free licence. For ourselves and on your behalf, we would like to thank the Institute for the enthusiasm that these prizes demonstrate for the RepRap project and for their magnificent generosity.
Congrats to Foresight Institute and Kartik Gada for establishing this interesting and substantial prize. There is another prize, too. Besides the Personal Manufacturing Prize, there is a Water Liberation Prize, described here:
The winner of the Water Liberation Prize of up to $50,000 will be the first person to invent a device that is either solar powered, manually cranked, or otherwise not dependent on the existence of an electrical grid, can produce at least 4 liters of potable (drinkable) water per day, either condensed from the air (as measured in approximate 50% ambient humidity) or filtered through a nanomembrane, and can be mass-produced (as demonstrated by a pilot run of no less than 100 units) for a cost of less than $5 per unit. The filter should be washable and re-usable, without requiring a periodic supply of new filters, as the device may be used in areas without access to a suitable distribution channel.
Vik Olliver, a RepRap hobbyist, created a PLA mold (of a Mighty RepRap Power Ring), filled it with melted pewter, let it cool, then used a hammer to chip off the PLA material. This is the first use of RepRap with metal casting that I'm aware of. In his blog post on the topic, Olliver implies that it might be possible to try it with metals with higher melting points like aluminum or bronze, with proper research. Here is a photograph of the completed ring:
Plaster of Paris (which was used to shield the PLA from the heat of the melted pewter) has a melting point of 2660 °F (1460 °C), but according to Olliver, using metals like molten aluminum, with a temperature of 1220 °F (660 °C) or greater can "cause plaster of Paris to decompose in undesirable ways and you need to research it properly."
For aluminum and bronze, you'd need investment, a type of plaster used by jewelers. According to the Plaster FAQ, it "will hang together just enough, after being brought to more than 1000 degrees F, to hold molten bronze and impart shape and fine detail, while still being friable enough to remove easily from the casting." For even higher temperatures, ceramic shells must be used.
There is lots of great activity happening at RepRap, with its superlative slogan, "wealth without money". The big news lately is the upcoming release of "RepRap II", also called Mendel. The first was Darwin. Here is a video of Mendel's first print:
The cost for the parts to build Mendel is approximately Â£395. However, it can self-replicate. Here's a description of the improvements of Mendel over Darwin:
And finally, here is a video of the 4-machine "RepRap Factory", which consists solely of machines dedicated to building parts for other machines:
Congratulations to everyone at RepRap on their work.